Lip reader, Nicola Hickling, has claimed that King Charles made a brutal 'dig' about Prince Harry to Queen Camilla during the Trooping the Colour event.

The Royal family marked King Charles’ official birthday with the annual Trooping the Colour ceremony in London where the monarch was joined by Prince William, Princess Catherine and their three children.

Senior working royals including Prince William, Kate Middleton, Princess Anne, Prince Edward and Queen Camilla will reportedly take part in the king's birthday parade.

Ahead of Saturday's festivities, King Charles III also honored a handful of celebrities and public figures, including David Beckham, Gary Oldman and Elaine Paige.

As per the British Army website, the ceremony of Trooping the Colour is thought to have first taken place during the reign of King Charles II in the 17th century. In 1748 it was decided that it would be used to mark the Sovereign’s official birthday.

Prince George, Princess Charlotte and Prince Louis made an appearance on the Buckingham Palace balcony for Trooping the Colour. See the best photos of the royal siblings.